Not that bad
I had low expectations before going to this. I only went because it was a 3 dollar ticket. It ended up being a pretty decent horror movie. The scenery is beautiful, the story is unique and makes sense, and not everything is spelled out for you.
Some parts weren't acted that well or were even kind of comical, but it would be tricky for the plot to move on without them. I.e. the kids' cliche looking drawings.